Endless-track vehicle



A ril 13 1926.

A. T. DAWSON ET AL ENDLESS TRACK VEHICLE Filad April 17 ream-ea Apr. is, 1926.

* UNITED srA TssrA-TENT OFFICE- 1 ARTHUR TREVOR DAwsoN AND'GEORGE THOMAS BUCKHAM, or WESTMINSTER, ENG-' LAND, ASSIGNORS To VICKERS LIMITED. 0): WESTMINSTER, ENGLAND, A BRITISH COMPANY.

ENDLESS-TRACK VEHICLE.-

Application filed April 17, 1925. Serial Nb. 23,8 0. v

To all whom it may concern:

Be it known that we, ARTHUR Tnnvon DAWSON and Gnonsn THOMAS BUoIrHAM, both subjects of the King of Great Britain,

residing at Vickers House, Broadway, Testminster, in the county of London, England,

have invented certain new and useful, Im

provements in. or Relating to Endless-Track Vehicles," on which application Nol 8,252 for Letters Patent was filed in Great Britain- April 1, 1924, and of which the following"v is a specification. A

This invention relates to endless track vehicles and has for its object to improvethe springing of the rollers running on the track.

According to the invention the axle of one roller and the axle of the next roller in the longitudinal direction of the track are connected to the vehicle frame by means of levers the inner ends of which are pivoted to part of the vehicle frame and the outer ends of which have interposedbetween them a spring which is energized by movement of one orthe other (or'both) of the levers when the rollers pass over an obstruction. The

'said levers are preferably of cranked form withthe portions at the angle pivoted upon the roller axles and with the ends of the horizontal limbs pivoted on part of the vehicle frame, whilst the upper ends of the vertical limbs of'the cranked, levers co-operate with one or more springs.

In order that the said lnvention may be clearly understood and readily carried into 7' position they occupy when the vehiclevis travelling over even ground.

Figure 2 is a section taken approximately on the line 22 of Figure 1, and

Figure 3'is a view similar to "Figure 1 showing the parts in the position they occupy when one of the rollers passes over an obstruction. 1 v

A is the vehicle frame, B is the endless track and C, C are some of the rollers running on the track. I) is one of the cranked levers the horizontal limb of whiclrflisv pivoted at A to part of the vehicle frame and D is the other cranked leverthe horizontal limbof which is also pivoted at A In the construction shown the rollers'a-re arranged in transversely connected pairs and the cranks are duplicated, that is to say cranked levers D, D are pivoted at dand (Z on the ends' of the axles of each pair of rollers. Insteadoof the said pairs of rollers, single rollers may, in certain circumstances, be used. c A A v The vertical limbs of the cranked levers are pivoted at d", cl to'cylinders E, E which are slidably dispo'sedwithin an outer cylinder F having at its centre part an internal flange or partition F serving as an abutment for the inner ends of two separate helical compression springs c, e the outer ends of which bear againstthe closed ends of the inner cylinders E, E The said outer cylinder is not attached to any fixed part so that'the two springs separated by the internal flan e. orl partition F act as v a single spring. he l upper parts of the vertical limbs of the cranked levers have rubber pads D", D which come against stops a, a on the vehicle frame to limit the movement of each cranked lever when the roller passes over any obstruction as shown in Figure 3.

It will be understood that all the rollers" that come into virtual contact with the ground are arranged to be sprung in the,

manner above described.

VVhat'we claim and desire LettersPatent of the United States'is 1. Inan endless track. vehicle, the combination with the endless track, of a-plurality;

of longitudinally spaced rollers running on said'track, a pluralityoflevrs, means for pivoting said. roller-s to said levers at points between the ends of the latter, means for pivoting one end of each lever to the vehicle frame and resilient means acting on the other end of each lever to oppose the up ward movements of the levers about their pivoted, ends.

2. In an endlesstrack vehicle, the combination with the endless track,*of a plurality.

of longitudinally Spaced rollers running on said track, a plurality of cranked levels with substantially horizontal limbs andfsubstantially vertical limbs, means forpivoting said rollers to Said levers at the portions at the angles of the cranks, means for pivotin the ends of the horizontal limbs'i to thevediicle to secure by :trame, and resilient means acting on the'vertical limbs to oppose the upward movements of said levers about the pivots of their horizontal limbs.

3. In an endless track VClllClG the combination with the endless track, of a plurality of longitudinally spaced rollers running on said track, a plurality of levers, means for pivoting said rollers to said levers at points between the ends of the latter, means for pivoting the contiguous ends of adjacent lovers to the frame and resilient means acting on the opposite ends of said levers to oppose the upward movements oi the levers about their pivoted ends.

l. In an endless track vehicle, the combination with the endless track, or a plurality of longitudinally spaced rollers running on said track, a plurality of lovers, means for pivoting said rollers to said levers at points between the ends of the latter, means for pivoting the contiguous ends of adjacent le vers to each other and to the frame and a spring interposed between the opposite ends of each pair of levers to oppose the upward movements of the levers about their pivoted ends.

5. In an endless track vehicle, the combination with the endless track, of a plurality of longitudinally spaced rollers running on said 1 track, a plurality of ranked lovers with substantially horizontal limbs and substantially vertical limbs and arranged in pairs with the horizontal limbs directed towards each other, means for pivoting said rollers to said levers at the portions at the angles of the cranks, means for pivoting the ends of said horizontal limbs to each other and to the vehicle frame and a spring interposed between the ends of each pair of vertical limbs to oppose the upward movements of said levers about the pivot-s of their horizontal limbs.

6. In an endless track vehicle, the combination with the elements claimed in claim 2, of resilient cushioning devices which at the termination of the up *ard movements of the cranked levers are compressed between the outer ends of the vertical arms of the said levers and parts of the vehicle frame by direct thrusts passing approximately through the axes ofthe rollers so that the said levers are not subjected to bending stresses when the said devices are in opje'ration.

"7. In anendless track vehicle the combination with the elements claimed in claim 2, of a resilient pad which is carried by the outer end oi the vertical arm of each or" the cranked levers and which, at the termination of the upward movement of each le er comes against part of the vehicle frame to compress said pad by a direct thrust pass ingapproximately through the axis'ot the roller carried by this lever so that the latter is not subjected to bendingstresses when said pad is being compressed;

ARTHUR TREVOR DAWSON. GEORGE THOMAS BUCKHAM; 

